Esters of oxypropylated acyl phenol monosulfides



United States Patent 2,695,917 Patented Nov. 30, 1954 ESTERS FOXYPROPYLATED ACYL PHENOL MONOSULFIDES Melvin De Groote, UniversityCity, Mo., assignor to Petrolite Corporation, a corporation of DelawareNo Drawing. Application January 21, 1952, Serial No. 267,518

11 Claims. (Cl. 260-475) 0 OH HO 0 it. it.

in which R1 and R2 are alkyl groups having 1 to carbon atoms and R3 andR4 are members of the group consisting of alkyl, aryl, alkoxyallryl,aroxyalkyl, aralkyl, alkaryl and cycloalkyl radicals. Such acyl phenolmonosulfide is treated with propylene oxide so the molecular weightbased on the hydroxyl value is within the range of 1000 to approximately7000. Such oxypropylation derivatives are invariably xylene-soluble, andwater-insoluble. When the molecular weight based on the hydroxyl valueis in the neighborhood of 1,000 or thereabouts the oxypropylationproduct is almost invariably kerosene-soluble. In fact, dependin on theparticular acyl phenol monosulfide subjected to oxypropylation, theproduct may be bacome kerosene-soluble at a lower range, for instance,700 or 800 molecular weight.

The most satisfactory monosulfides suitable as initial reactants arepreferably those in which the acyl radical is derived from adetergent-forming acid selected from the group of higher fatty acids andresinic acids, such as abietic acid and naphthenic acids. Thedetergentforming monocarboxy acids have at least 8 and not over 22carbon atoms. Satisfactory monosulfidc suitable as initial reactantsalso may contain acyl radicals derived from a lower fatty acid. Theexpression lower fatty acids refers to those having less than 8 carbonatoms. The most suitable phenols for conversion into the monosulfidesare substituted phenols in which the hydrocarbon substituent has atleast 4 carbon atoms and not over 14 carbon atoms.

These acyl phenol monosulfides which are subjected to oxypropylationprior to esterification may be obtained by well known methods. Theirpreparation is described, for example, in U. S. Patent No. 2,319,662,dated May 18, 1943, to Cook et al. My preference is to use acyl phenylmonosulfides in which R1 and R2 are the same and have 4 to 16 carbonatoms, i. e.. are derivatives of butylphenol, amylphenol, nonylphenol,decylphenol, dodecylphcncl, cardanol and hydrogenated cardanol.Obviously, the substituent need not be limited to the para position, butthis appears preferable. Indeed, when derived from cardanol orhydrogenated cardanol the substituent is in the meta position.Ortho-substituted amyl or butyl phenol may be used very satisfactorily.It is my preference to use materials in which the acyl radical is thesame and is derived from a higher fatty acid having 8 to 13 carbon atomsalthough excellent results have been obtained when derived from variousnaphthenic acids.

alkylene oxides including propylene oxide.

Purely as a matter of convenience the acyl phenol l'fiOIlOSllifidCSpreviously described may be represented t us:

For convenience, then, the oxypropylated derivative may be representedby the following formula:

with the proviso that n and 12' represent Whole numbers which when addedtogether equal a sum varying from 15 to 80, and the acidic esterobtained by reaction with the polycarboxy acid may be indicated thus:

in which the characters have their previous significance and n" is awhole number not over 2, and R is the radical of the polycarboxy acidcoon (COOH)n" and preferably free from any radicals having more than 8uninterrupted carbon atoms in a single group, and with the furtherproviso that the parent diol prior to esterification be preferablyXylene-soluble, and better still, kerosene-soluble. The diols hereinemployed as raw materials are water-insoluble.

Numerous water'insoluble compounds susceptible to oxyalkylation, andparticularly to oxyethylation, have been oxyethylated so as to produceeffectvie surfaceactive agents, which, in some instances at least, alsohave had at least modest demulsifying property. Reference is made tomonomeric compounds having a hydrophobe group containing, for example 8to 32 carbon atoms, and a reactive hydrogen atom, such as the usualacids, alcohols, alkylated phenols, amines, amides, etc. In suchinstances, invariably the approach was to introduce a counter-balanceeffect by means of the addition of a hydrophile group particularlyethylene oxide, or, in some instances, glycide, or perhaps a mixture ofboth hydrophile groups and hydrophobe groups, as, for example, in theintroduction of propylene oxide along with ethylene oxide. On anothertype of material a polymeric material, such as resin, has been subjectedto reaction with In such instances certain derivatives obtained frompolycarboxy acids have been employed.

Obviously, thousands and thousands of combinations, starting withhundreds of initial Water-insoluble materials, are possible. Explorationof a large number of raw materials has yielded only a few which appearto be commercially practical and competitive with available demulsifyingagents.

Acyl phenol monosulfides of the kind previously de scribed happen to beone class of suitable compound. On the other hand, somewhat relatedproducts, for instance, sulfides derived from resorcinol which has beentreated with one mole of ethylene oxide so as to convert the phenolichydroxyl to an alkylene hydroxyl and subsequently esterified, have beenexamined and found to be comparatively unsatisfactory as compared withthe acyl phenol monosulfides herein described and an initial examinationof the structure of these two types of compounds shows they have much incommon. The reason or reasons for this difference is merely a matter ofspeculation. These acyl phenol m-onosulfides are comparatively expensiveand obviously if a cheaper dihydroxylated intermediate of approximatelythe same general characteristics would serve nothing would be gained bythe employment of a more expensive raw material.

Exhaustive oxypropylation renders a water-soluble materialwater-insoluble. Similarly, it renders a keroseneinsoluble materialkesosene-soluble; for instance, reference has been made to the fact thatthis is true, for example, using polypropylene glycol 2,000. Actually,it is true with polypropylene glycol having lower molecular weights than2,000. These materials are obtained by the oxypropylation of awater-soluble kerosene-insoluble material, i. e., either water orpropyleneglycol.

Just Why certain different materials which are waterinsoluble to startwith, and which presumably are rendered more water-insoluble byexhaustive oxypropylation (if such expression as more wateuinsoluble hassignificance) can be converted into a valuable surface-active agent, andparticularly a valuable demulsifying agent, by reaction with apolycarboxy acid which does not particularly affect the solubility oneway or the other dgpending upon the selection of the acidis unexplainae.

Although the herein described products have a number of industrialapplications, they are of particular value for resolving petroleumemulsions of the water-in-oil type that are commonly referred to as cutoil, roily oil, emulsified oil, etc., and which comprise fine dropletsof naturally-occurring waters or brines dispersed in a more or lesspermanent state throughout the oil which constitutes the continuousphase of the emulsion. This specific application is described andclaimed in my copendi9n5g2 application, Serial No. 267,517, filedJanuary The new products are useful as wetting, detergent and levelingagents in the laundry, textile and dyeing industries; as wetting agentsand detergents in the acid washing of building stone and brick; aswetting agents and spreaders in the application of asphalt in roadbuilding and the like; as a flotation reagent in the flotationseparation of various aqueous suspensions containing negatively chargedparticles, such as sewage, coal washing waste water, and various tradewastes and the like; as germicides, insecticides, emulsifying agents,as, for example, for cosmetics, spray oils, water-repellent textilefinishes, as lubricants, etc.

For convenience, what is said hereinafter will be divided into fourparts:

Part 1 will be concerned with the oxypropylated derivatives, i. e.,diols, of the previously described acyl phenol monosulfides;

Part 2 will be concerned with the preparation of esters from theaforementioned diols or dihydroxylated compounds;

Part 3 will be concerned with the nature of the products obtained byoxypropylation in light of the fact that certam SIdE ICaCtIOHSinvariably and inevitably occur, and Part 4 will be concerned withcertain derivatives which can be obtained from these acidic esters andwhich, in

turn, are valuable for a variety of purposes.

PART 1 oxypropylation, like other oxyalkylation operations,

should be carried out with due care, in equipment V Example 1a Thestarting material was 2-butyryl-4-amyl phenol monosulfide. Theparticular autoclave employed was one having a maximum capacity of aboutgallons, or approximately 125 pounds of reaction mass. The speed of thestirrer could be varied from 150 to 350 R. P. M. 30 pounds of the2-butyryl-4-amyl phenol monosulfide were charged into the autoclavealong with 5 pounds of finely pulverized caustic soda. No solvent wasadded in this particular run, although on smaller runs small amounts ofxylene or other suitable solvent have been added, for instance, aboutone-half as much xylene as the monosulfide. Needless to say, one couldadd not only xylene but, for that matter, any conventional solvent. Evenif the sulfide is not completely soluble in the selected solvent, itstill produces a slurry that is sometimes more convenient to handle.

The reaction pot was flushed out with nitrogen and the autoclave sealedand the automatic devices set for injecting 65 pounds of propylene oxidein approximately three hours. At the end of this time the stirring wascontinued for another half hour. The pressuring device was set for amaximum of to pounds per square inch. Actually in the course of thereactions due to the presence of a generous amount of catalyst thereaction pressure never exceeded the indicated maximum of 35 pounds.Experience has shown that sometimes in the initial stages the reactiontakes place at a lower pressure and sometimes tends to go over the35-pound pressure. As it happened in this particular series ofoxypropylations the pressure seemed to stay within the range of 30 to 35pounds throughout the entire series. For this reason no furtherreference will be made to operating pressures in the subsequent stages.Usually when one sets the gauge for a maximum pressure the bulk of thereaction can take place and quite frequently does take place at a lowerpressure. Such lower pressure is the result, as a rule, of

(a) Activity of the reactant,

(b) Presence of a sizable amount of catalyst,

(c) Eflicient agitation, and

(d) A fairly long time of reaction.

The propylene oxide was added comparatively slowly and, more important,the selected temperature, although moderately higher than the boilingpoint of water, was not excessively high; for instance, in thisparticular stage, and in fact in all subsequent stages, reaction tookplace within the range of 130 to 135 C. For this reason no furtherreference will be made in Examples 2a through to temperature ofreaction.

At the completion of the reaction a sample was taken and oxypropylationproceeded as in Example 20, followmg:

Example 2a pounds of the reaction mass identified as Example In,preceding, and equivalent to 18 pounds of the original monosulfide, 39pounds propylene oxide, and 3 pounds caustic soda, were permitted toremain in the reaction vessel. Without the addition of any more catalyst39 pounds of propylene oxide were added. The oxypropylation wasconducted in the same manner as employed in Example la, preceding,particularly as far as temperature and pressure were concerned. Thereaction time was somewhat longer. to wit, 4 hours. This was due to thefact presumably that the alkali concentration was somewhat lower. At theend of the reaction period part of the reaction mass was withdrawn as asample and oxypropylation continued with the remainder of the reactionmass as described in Example 3a, following.

Example 3a 60 pounds of the reaction mass identified as Example 2a,preceding, and equivalent to 11.4 pounds of the original monosulfide,46.7 pounds of propylene oxide, and 1.9 pounds of caustic soda, werepermitted to remain in the reaction vessel. 38 pounds of propylene oxidewere introduced in the third stage. The time required was 6 hours. Theconditions as far as temperature and pressure were concerned were thesame as in the previous two examples. After completion of the reaction,part of the reaction mass was withdrawn and the remainder subjected tofurther oxypropylation as described in Example 4a, following.

Example 4a 60 pounds of the reaction mass identified as Example 3a,preceding, and equivalent to 7.0 pounds of the monosulfide and 51.8pounds of propylene oxide, and 1.2 pounds of caustic soda, werepermitted to remain in the autoclave. Without the addition of any morecaustic at any stage, not only in this step but in the previous steps,there were added 25 pounds of propylene oxide. The time required to addthe oxide was 8 hours. Conditions in regard to temperature and pressurewere the same as in the preceding examples.

In this particular series of examples the oxypropylation was stopped atthis stage. In other series I have continued the oxypropylation so thetheoretical molecular weight was approximately 8,700 to 10,200 and thehydroxyl molecular weights varied from about 3,900 to approximately4,600. Other weights, of course, are obtainable using the sameprocedure.

What is said herein is presented in tabular form in Table 1, immediatelyfollowing, with some added information as to molecular weight and as tosolubility of the reaction product in water, xylene, and kerosene.

active towards polycarboxy acids, presumably would have the effect ofdecreasing the apparent hydroxyl value.

In the present instance the oxypropylated derivative was more complexthan the usual glycol or the glycollike compound involving carbon,hydrogen and oxygen only. However, the presence of solvent in theoxypropylated derivative does not detract from what has been saidpreviously as to the general considerations involved.

TABLE 1 Composition before Composition at end MaK Max. T

pres, une, Phenol Oxide Phenol Oxide lbs. sq hrs. sulfide amt Oats Theosulfide amt H) in lbs." lyst, lbs. M. W. lbs." lyst, lbs. mol. wt.

45. 0 3. 0 1, 604 45. 0 55. 0 3. 0 l, 135 130-135 30-35 4 27. 6 33. 6 1.8 2, 680 27. 6 75. 0 l. 8 l, 496 130-135 30-35 5% 10. 3 54. 1 0. 6 5,900 10. 3 74. l 0. 6 2, 988 130-135 30-35 8 50. 0 2. 5 1, 780 50. 0 50.0 2. 5 1, 248 130-135 30-35 3% 35. 4 35. 4 1. 7 2, 530 35. 4 65. 4 l. 71, 553 130-135 30-35 3% 23. 3 43. 1 1. 1 3, 680 23. 3 73. l 1. 1 2, 190130-135 30-35 4% The starting material in Examples 1a through 4a was2-butyryl-4-amyl pho'uol monosulfide. The starting material in Examples5a through 8a was 2-lauroyl-4-an1ylphenol mnuosulfide. The startingmaterial in Examples 9:; through 1241. was 2-stearoyl'4amylolteuolmonosulfide. The starting material in Examples 13a through 16a was6-stearoyl-2amylphenol monosuliide.

As far as solubility is concerned all the products were water-insolublein all stages but were invariably xylenesoluble. In the higher stages ofoxypropylation, for instance, at a hydroxyl molecular weight of about1500 or thereabouts they were kerosene-soluble.

Ordinarily in the initial oxypropylation of a simple compound, such asethylene glycol or propylene glycol, the hydroxyl molecular weight isapt to approximate the theoretical molecular weight, based oncompleteness of reaction, if oxypropylation is conducted slowly and at acomparatively low temperature, as described. In this instance, however,this does not seem to follow, as it is noted in the preceding table thatat the point where the theoretical molecular weight is approximately2,000, the hydroxyl molecular weight is only about one-half this amount.This generalization does not necessarily apply where there are morehydroxyls present, and in the present instance the results are somewhatpeculiar when compared with simple dihydroxylated materials asdescribed, or with phenols.

The fact that such pronounced variation takes place between hydroxylmolecular weight and theoretical molecular weight, based on completenessof reaction, has been subjected to examination and speculation, but nosatisfactory rationale has been suggested.

One suggestion has been that one hydroxyl is lost by dehydration andthat this ultimately causes a break in the molecule in such a way thattwo new hydroxyls are formed. This is shown after a fashion in a highlyidealized manner in the following way:

In the above formulas the large X obviously is not intended to signifyanything except the central part of a The final products at the end ofthe oxypropylation step were somewhat viscous liquids, about as viscousas ordinary polypropylene glycols, with a dark amber tint. This color,of course, could be removed if desired by means of bleaching clays,filtering chars, or the like. The products were slightly alkaline due tothe residual caustic soda. The residual basicity due to the catalystwould be the same if sodium methylate had been employed.

Needless to say, there is no complete conversion of propylene oxide intothe desired hydroxylated compounds. This is indicated by the fact thatthe theoretical molecular weight, based on a statistical average, isgreater than the molecular weight calculated by usual methods on basisof acetyl or hydroxyl value. This is true even in the case of a normalrun of the kind noted previously. It is true also in regard to theoxypropylation of simple compounds, for instance, propylene glycol orethylene glycol.

Actually, there is no completely satisfactory method for determiningmolecular weights of these types of compounds with a high degree ofaccuracy when the molecular weights exceed 2,000. In some instances theacetyl value of hydroxyl value serves as satisfactorily as an index tothe molecular weight as any other procedure, subject to the abovelimitations, and especially in the higher molecular weight range. If anydifliculty is encountered in the manufacture of the esters, as describedin Part 2, the stoichiometrical amount of acid or acid compound shouldbe taken which corresponds to the indicated acetyl or hydroxyl value.This matter has been discussed in the literature and is a matter ofcommon knowledge and requires no further elaboration. In fact, it isillustrated by some of the examples appearing in the patent previouslymentioned.

PART 2 As previously pointed out, the: present invention is concernedwith acidic esters obtained from the oxypropylated derivatives describedin Part 1, preceding, and polycarboxy acids, particularly tricarboxyacids like citric, and dicarboxy acids such as adipic acid, phthalicacid, or anhydride, succinic acid, diglycollic acid, sebacic acid,azelaic acid, aconitic acid, maleic acid, or anhydride, citraconic acidor anhydride, maleic acid or anhydride adducts, as obtained by theDiels-Adler reaction from products such as maleic anhydride, andcyclopentadiene. Such acids should be heat-stable so they are notdecomposed during esterification. They may contain as man as 36 carbonatoms as, for example, the acids obtained by dimerization of unsaturatedfatty acids, unsaturated monocarboxy fatty acids, or unsaturatedmonocarboxy acids having 18 carbon atoms. Reference to the acid in thehereto appended claims obviously includes the anhydrides or any otherobvious equivalents. My preference, however, is to use polycarboxy acidshaving not over 8 carbon atoms.

The production of esters including acid esters (fractional esters) frompolycarboxy acids and glycols, or other hydroxylated compounds, is wellknown. Needless to say, various compounds may be used such as the lowmolal ester, the anhydride, the acyl chloride, etc. However, for purposeof economy it is customary to use either the acid or the anhydride. Aconventional pro cedure is employed. On a laboratory scale one canemploy a resin pot of the kind described in U. S. Patent No. 2,499,370,dated March 7, 1950, to DeGroote and Keiser, and particularly with onemore opening to permit the use of a porous spreader if hydrochloric acidgas is used as a catalyst. Such device or absorption spreader consistsof minute alundum thimbles which are connected to a gas tube. One canadd a sulfonic acid such as paratoluene sulfonic acid as a catalyst.There is some objection to this because in some instances there is someevidence that this acid catalyst tends to decompose or rearrangeheat-oxypropylated compounds. It is particularly likely to do so if theesterification temperature is too high. In the case of polycarboxy acidssuch as diglycollic acid which is strongly acidic there is no need toadd any catalyst. The use of hydrochloric acid gas has one advantageover paratoluene sulfonic acid and that is that at the end of thereaction it can be removed by flushing out with nitrogen, whereas thereis no reasonably convenient means available of removing the paratoluenesulfonic acid or other sulfonic acid employed. If hydrochloric acid isemployed one need only pass the gas through at an exceedingly slow rateso as to keep the reaction mass acidic. Only a trace of acid need bepresent. I have employed hydrochloric acid gas or the aqueous aciditself to eliminate'the initial basic material. My preference, however,is to use no catalyst whatsoever and to insure complete dryness of thediol, as described in the final procedure just preceding Table 2.

The products obtained in Part 1, preceding, may contain a basiccatalyst. As a general procedure, I have added an amount ofhalf-concentrated hydrochloric acid considerably in excess of what isrequired to neutralize the residual catalyst. The mixture is shakenthoroughly and allowed to stand overnight. It is then filtered andrefluxed with the xylene present until the water can be separated in aphase-separating trap. As soon as the product is substantially free fromwater the distillation stops. This preliminary step can be carried outin the flask to be used for esterification. If there is any furtherdeposition of sodium chloride during the reflux stage, needless to say,a second filtration may be required. In any event, the neutral orslightly acidic solution of the oxypropylated derivatives described inPart 1 is then diluted further with sufiicient xylene, decalin,petroleum solvent, or the like, so that one has obtained approximately a45%-65% solution. To this solution there is added a polycarboxylatedreactant, as previously described, such as phthalic anhydride, succinicacid, or anhydride, diglycollic acid, etc. The mixture is refluxed untilesterification is complete, as indicated by elimination of Water or dropin carboxyl value. Needless to say, if one produces a half-ester from ananhydride such as phthalic anhydride, no water is eliminated. However,if it is obtained from diglycollic acid, for example, water iseliminated. All such procedures are conventional and have been sothoroughly described in the literature that further consideration willbe limited to a few examples and a comprehensive table.

Other procedures for eliminating the basic residual catalyst, if any,can be employed. For example, the oxyalkylation can be conducted inabsence of a solvent or the solvent removed after oxypropylation. Suchoxypropylation end-product can then be acidified with just enoughconcentrated hydrochloric acid to just neutralize the residual basiccatalyst. To this product one can then add a small amount of anhydroussodium sulfate (stiflicient in quantity to take up any water that ispresent) and then subject the mass to centrifugal force so as toeliminate the hydrated sodium sulfate and probably the sodium chlorideformed. The clear, somewhat viscous, straw-colored amber liquid soobtained may contain a small amount of sodium sulfate or sodiumchloride, but in any event is perfectly acceptable for esterification inthe manner described.

It is to be pointed out that the products here described are notpolyesters in the sense that there is a plurality of both diol radicalsand acid radicals; the product is characterized by having only one diolradical.

In some instances and, in fact, in many instances, I have found that inspite of the dehydration methods employed above, a mere trace of waterstill comes through, and that this mere trace of water certainlyinterferes with the acetyl or hydroxyl value determination, at leastwhen a number of conventional procedures are used and may retardesterification, particularly where there is no sulfonic acid orhydrochloric acid present as a catalyst. Therefore, I have preferred touse the following procedure: I have employed about 200 grams of the diolcompound, as described in Part 1, preceding; I have added about 60 gramsof benzene and refluxed this mixture in the glass resin pot, using aphase-separating trap, until the benzene carried out all the waterpresent as water of solution or the equivalent. Ordinarily thisrefluxing temperature is apt to be in the neighborhood of 130 C. topossibly 150 C. When all this water or moisture has been removed I alsowithdraw approximately grams, or a little less, benzene and then add therequired amount of the carboxy reactant and also about 150 grams of ahigh-boiling aromatic petroleum solvent. These solvents are sold byvarious oil refineries and, as far as solvent effect goes, act as ifthey were almost completely aromatic in character. Typical distillationdata in the particular type I have employed and found very satisfactoryis the following:

I. B. P., 142 C. ml., 242 C. 5 ml., 200 C. ml., 244 C. 10 ml., 209 C.ml., 248 C. 15 ml., 215 C. ml., 282 C. 20 ml., 216 C. ml., 252 C. 25ml., 220 C. ml., 260 C. 30 ml., 225 C. ml., 264 C.

35 ml., 230 C. 40 ml., 234 C. ml., 280 C. 45 ml., 237 C. ml., 307 C.

After this material is added refluxing is continued and, of course, isat a high temperature, to Wit, about to C. If the carboxy reactant is ananhydride, needless to say, no water of reaction appears; if the corboxyreactant is an acid, water of reaction should appear and should beeliminated at the above reaction temperature. If it is not eliminated, Isimply separate out another 10 to 20 cc. of benzene by means of thephase-separating trap and thus raise the temperature to or C., or evento 200 C., if need be. My preference is not to go above 200 C.

Actually there is considerable convenience in using a mixture of about70 parts of a high-boiling petroleum distillate of the kind described,and 30 parts xylene. Indeed, reference in the appended table to xylenesolvent No. 7 refers to this particular mixture.

The use of such solvent is extremely satisfactory, provided one does notattempt to remove the solvent subsequently, except by vacuumdistillation, and provided there is no objection to a little residue.Actually, when these materials are used for a purpose such asdemulsification, the solvent might just as well be allowed to remain. Ifthe solvent is to be removed by distillation, and particularly vacuumdistillation, then the high boiling aromatic petroleum solvent mightwell be replaced by some more expensive solvent, such a decalin or analkylated decalin which has a rather definite or close range boilingpoint. The removal of the solvent, of course, is purely a conventionalprocedure and requires no elaboration.

When starting with the high molal glycol, as herein described, as one ofthe raw materials I have found that that xylene by itself is practicallyor almost as satisfactory as other solvents or mixtures. Decalin also issuitable. Actually, at times there is some advantage in using a mixtureof a high-boiling aromatic petroleum solvent and xylene in preparationof other typical examples of the kind herein described.

The data included in the subsequent tables, i. e., Tables 2 and 3, areself-explanatory and very complete and it is believed no furtherelaboration is necessary.

85 ml., 270 C.

TABLE 2 Ex. No. Ex. No. Theo Theo. Mol. wt. Amt. of g, P of of mol wthydr. Actual based on hyd. Polycarboxy g g 801d hydmxy H value or H. V.actual cmpd. reactant reactant ester cmp H. C. H. V. (2 (grs 1, 580 71110 1,020 510 Diglycolic acid 134 1, 580 71 110 1, 020 510 Phthalicanhydride. 148 1, 580 71 110 1, 020 510 Malelc anhydride 98 1. 580 71110 1, 020 510 Oxalic acid 126 2, 548 44 78 l, 438 359. 5 Diglycolicacid.- 67 2, 548 44 78 1, 438 359. 5 Phthalic anhydrrde. 74 2, 548 4.478 1, 438 359. 5 Maleic anhydridc-... 49 2, 548 44 78 1, 438 359. 5Aconitic acid 87 4, 198 26. 7 57. 0 1, 970 492. 5 Diglycolic acid 674,198 26. 7 57. 0 1, 970 492. 5 Phthalic anhydnde. 74 4, 198 26. 7 57. 01, 970 492. 5 Maleic anhydride. 49 4, 198 26. 7 57.0 1, 970 Aconiticacid. 87 5, 960 18. 8 49. 7 2, 260 67 5, 960 18. 8 49. 7 2, 260 1d 74 5,960 13. 8 49. 7 2, 260 565 Maleic anhydride.. 49 5, 960 18. 8 49. 7 2,260 565 Oitraconic acid. 56 1, 604 70 94.8 1, 185 592. 5 Diglycolic acid134 1, 604 70 94. 8 1,185 592. 5 Phthalic anhydride. 134 1, 604 70 94. 81, 185 592. 5 Maleic anhydrida... 98 1, 604 70 94. 8 1, 185 592. 5Aconitic acid 174 2. 680 41. 8 75 1, 496 374 Diglycolic acid 67 2, 68041. 8 75 1, 496 374 Phthalic anhydrrdm 74 2, 680 41. 8 75 1,496 374Maleic anhydride- 49 2, 680 41. 8 75 1, 496 374 Aconitic acid.. 87 4,520 24. 8 54. 8 2, 044 511 Diglycolic acid 67 4, 520 24.8 54. 8 2, 044511 Phthalic anhydrrde. 74 4, 520 24. 8 54. 8 2, 044 511 Maleicanhydrida". 49 4, 520 24. 8 54. 8 ,044 511 Oxalic acid 63 5, 900 19 37.6 2, 988 373 Diglycolic acid 33. 5 5, 900 19 37. 6 2, 988 373 Phthalicanhydride. 37 5, 900 19 37. 6 2, 988 373 Maleic anhydride.-.. 24. 5 5,900 19 37. 6 2, 988 373 Succinic acid.-. 29. 6 1, 780 63. 2 89. 8 1, 248312 Diglycolic acid" 67 1, 780 63. 2 89.8 1,248 312 Phthalic anhydride.74 1, 780 63. 2 89. 8 1, 248 312 Maleic anhydride... 49 1, 780 63. 2 89.8 1, 248 312 Oitraconic acid 56 2, 530 44. 3 72. 2 1, 554 389 Diglycolicacid 67 2, 530 44. 3 72. 2 1, 554 389 Phthalic anhydride 74 2, 530 44. 372.2 1, 554 389 Maleic anhydr1de..- 49 2, 530 44. 3 72.2 1, 554 389Succinic acid 59 3, 680 30. 5 51. 2 2, 996 274 Diglycolic acid 33. 53,680 30. 5 51. 2 2, 996 274 Phthallc anhydride... 37 3, 680 30. 5 51. 22, 996 274 Maleic anhydrlde-. 44. 5 3, 680 30. 5 51. 2 2, 996 274Succinic acid.-- 29. 5 6, 060 18. 5 34. 6 3, 250 325 Diglycolic acid 26.8 6, 060 18. 5 34. 6 3, 250 325 Maleic anhydride 19. 6 6, 060 18. 5 34.6 3, 250 325 Phthalic anhydride. 29. 6 6, 060 18. 5 34. 6 3, 250 325Oxalic Acid 25. 2 l, 690 66. 4 107 1, 050 525 Diglycolic acid 134 1, 69066. 4 107 1,050 525 Phthalic anhydride. 148 1, 690 66. 4 107 1, 050 525Aconitie acid 174 1, 690 66. 4 107 1, 050 525 Citraconic acid 112 3, 02037. 2 76.3 1, 490 367 Diglycolic acid 67 3, 020 37. 2 76. 3 1, 490 367Phthalic anhydride. 74 3, 020 37. 2 76. 3 1, 490 367 Aconitic acid 87 3,020 37. 2 76. 3 1, 490 367 Succinie acid 56 4, 810 23. 50. 2 2, 236 280Diglycolic acid 33. 5 4, 810 23.35 50.2 2, 236 280 Phthalic anhydride.37 4, 810 23. 35 50. 2 2, 236 280 Aconitic acid 43. 5 4, 810 23. 35 50.22, 236 280 Succinic acid..- 28 7, 770 14. 39. 3 2, 858 357 Diglygolicacid 33. 5 7, 770 14. 45 39. 3 2,858 357 Phthalic anhydride. 37 7, 77014. 45 39. 3 2, 858 357 Aconitic acid 43. 5 7, 770 14. 45 39. 3 3, 858357 Succinic acid 28 The procedure for manufacturing the esters has beenillustrated by preceding examples. It for any reason reaction does nottake place in a manner that is acceptable, attention should be directedto the following details:

(a) Recheck the hydroxyl or acetyl value of the oxypropylated high molalglycol as in Part 1, preceding;

If the reaction does not proceed with reasonable speed, either raise thetemperature indicated or else extend the period of time up to 12 or 16hours if need be;

(c) If necessary, use /2 of paratoluene sulfonic acid, or some otheracid, as a catalyst; and

(d) If the esterification does not produce a clear prod uct, a checkshould be made to see if an inorganic salt such as sodium chloride orsodium sulfate is not precipitating out. Such salt should be eliminated,at least for exploration experimentation, and can be removed byfiltering.

Everything else being equal, as the size of the molecule increases andthe reactive hydroxyl radical represents a smaller fraction of theentire molecule, more diificulty is involved in obtaining completeesterification.

Even under the most carefully controlled conditions of oxypropylationinvolving comparatively low temperatures and long time of reaction,there are formed certain compounds whose compositions are still obscure.Such side reaction products can contribute a substantial proportion ofthe final cogeneric reaction mixture. Various suggestions have been madeas to the nature of these compounds, such as being cyclic polymers ofpropylene thereof, i. e., of an aldehyde, ketone, or allyl alcohol. 1

In some instances an attempt to react the stoichiometric amount of apolycarboxy acid with the oxypropylated derivative results in an excessof the carboxylated reactant, for the reason that apparently underconditions of reaction less reactive hydroxyl radicals are present thanindicated by the hydroxyl value. Under such circumstances there issimply a residue of the carboxylic reactant which can be removed byfiltration, or, if desired, the esterification procedure can berepeated, using an appropriately reduced ratio of carboxylic reactant.

Even the determination of the hydroxyl value and conventional procedureleaves much to be desired, due either to the cogeneric materialspreviously referred to, or, for that matter, the presence of anyinorganic salts or propylene oxide. Obviously this oxide should beeliminated.

The solvent employed, if any, can be removed from the finished ester bydistillation, and particularly vacuum distillation. The final productsor liquids are generally from almost black or reddish-black to darkamber in color, and show moderate viscosity. They can be bleached withbleaching clays, filtering chars, and the like. However, for the purposeof demulsification or the like, color is not a factor and decolorizationis not justified.

TABLE 3 Amt. Maximum Time of 1 Ex. No. of solventsolesterifiesterifiacid e e vent cation cation 5 (grs.) temp, 0. (hrs.)

Xylene, solvent 7.- 626 160-165 6 18 608 145-150 4 582 170-175 7 54 417100-170 6 9 433 170-180 6 408 140-145 5 437 170-175 6 9 550 170-175 6 9566 165-175 6 542 145-150 5 10 570 170-175 0 9 623 170-175 8 9 639170-17 5 8 614 145-150 5 612 170-175 8 9 708 170-175 4 18 20 740 170-1754 090 145-150 4 766 170-175 4 18 532 170-175 5% 0 448 170-17 5 6 r 423150-160 5 452 170-175 8 9 569 170-175 5 9 585 170-175 6 560 145-150 5547 170-175 8 27 402 170-175 6 4. 5 410 170-175 6 9 397 130-140 0 all398 170-175 9 370 160-165 4 386 170-175 4 361 130-140 4 359 170-175 4447 150-160 4% 9 9 463 155-160 5 438 130-140 4 439 150-155 6 9 303150-160 5 4. 5 311 165-170 5 318 130-135 4% 299 150-160 7 4 5 348150-155 8 .5 6 348 130-135 5 355 150-160 8 339 150-155 8 10. S 640160-165 0 18 673 100-165 0 680 100-105 0 18 4a 620 160-165 6 18 425160-170 8 9 438 160-170 8 445 160-170 8 0 414 160-170 8 9 309 160-170 84. 5 317 160-170 8 319 160-170 8 4. 5 304 160-170 8 4. 5 386 165-180 84. 5

In the above instances I have permitted the solvents to remain presentin the final reaction mass. In other instances I have followed the sameprocedure, using decalin or a mixture of decalin or benzene in the samemanner and ultimately removed all the solvents by vacuum distillation.

PART 3 In the hereto appended claims the demulsifying agent is describedas an ester obtained from a polyhydroxylated material prepared from thedescribed diols. If one were concerned with a monohydroxylated materialor a dihydroxylated material one might be able to write a formula whichin essence would represent the particular product. However, in a morehighly hydroxylated material the problem becomes increasingly moredifficult for reasons which have already been indicated in connectionwith Oxypropylation and which can be examined by merely considering forthe moment a monohydroxylated material.

Oxyalkylation, particularly in any procedure which involves theintroduction of repetitious ether linkages, i. e., excessiveoxyalkylation, using, for example, ethylene oxide, propylene oxide,etc., runs into difficulties of at least two kinds; (a) formation of acogeneric mixture rather than a single compound, and (b) excessive sidereactions or the like. The former phase will be considered in theparagraphs following. As to the latter phase, see U. S. Patent No. 2,236,919, dated April 1, 1941, to Reynhart.

Oxypropylation involves the same sort of variations as appear inpreparing high molal polypropylene glycols. Propylene glycol has asecondary alcoholic radical and a primary alcohol radical. Obviouslythen polypropylene glycols could be obtained, at least theoretically, inwhich two secondary alcoholic groups are united or a secondary alcoholgroup is united to a primary alcohol, group, etherization beinginvolved, of course, in each instance. Needless to say, the samesituation applies when one has oxypropylated polyhydric materials having4 or more hydroxyls, or the obvious equivalent.

Usually no eflort is made to differentiate between oxypropylation takingplace, for example, at the primary alcohol radical or the secondaryalcohol radical. Actually, when such products are obtained, such as ahigh molal propylene glycol or the products obtained in the mannerherein described one does not obtain a single derivative such asIIO(RO)71H or -(RO)7.H in which n has one and only one value, forinstance, 14, 15 or 16, or the like. Rather, one obtains a cogenericmixture of closely related or touching homologues. These materialsinvariably have high molecular weights, and cannot be separated from oneanother by any known procedure, without decomposition. The proportion ofsuch mixture represents the contribution of the various individualmembers of the mixture. On a statistical basis, of course, 11 can beappropriately specified.

It becomes obvious that when carboxylic acidic esters are prepared fromsuch high molal molecular weight materials that the ultimateesterification product must, in turn, be a cogeneric mixture. Likewise,it is obvious that the contribution to the total molecular weight madeby the polycarboxy reactant is small. Thus, one might expect that theeffectivness of the demulsifier in the form 0 of the acidic fractionalester would be comparable to the esterified hydroxylated material.Remarkably enough, in practically every instance the product isdistinctly better, and in the majority of instances much more efiective.

PART 4 As pointed out previously, the final product obtained is afractional ester having free carboxyl radicals. Such product can be usedas an intermediate for conversion into other derivatives which areetfective for various purposes, such as the breaking of petroleumemulsions of the kind herein described. For instance, such product canbe neutralized with an amine so as to increase its water-solubility suchas triethanolamine, tripropanolamine, oxyethylated triethanolamine, etc.Similarly, such product can be neutralized with some amine which tendsto reduce the water-solubility such as cyclohexylamine, benzylamine,decylamine, tetradecylamine, octadecylamine, etc. Furthermore, theresidual carboxyl radicals can be esterified with alcohols, such as lowmolal alcohols, methyl, ethyl, propyl, butyl, etc., and also high molalalcohols, such as octyl, decyl, cyclohexanol, benzyl alcohol, octadecylalcohol, etc. Such products are also valuable for a variety of purposesdue to their modified solubility. This is particularly true wheresurface-active materials are of value and especially in demulsificationof water-in-oil emulsions.

Having thus described my invention, what I claim as new and desire tosecure by Letters Patent, is:

1. Hydrophile synthetic products; said hydrophile synthetic productsbeing characterized by the following formula:

I ll RO(C:;HoO),. CR(COOH)n in which n" is a whole number not over 2,and in which 19-0 is the divalent radical obtained by the removal of thephenolic hydrogen atoms from an acyl phenol monosulfide of the formulapl) OH HO f Ra-C- o-R,

in which R1 and R2 are alkyl groups having 1 to carbon atoms and R3 andR4 are members of the group consisting of lower alkyl radicals andcarbon linked radicals of monocarboxy detergent-forming acids having atleast 8 and not more than 22 carbon atoms; n and 11' represent wholenumbers which when added together equal a sum varying from 15 to 80, andR is the radical of a polycarboxy acid selected from the groupconsisting of acyclic and isocyclic polycarboxy acids having not morethan 8 carbon atoms and composed of carbon, hydrogen and oxygen of theformula:

COOH

in which n" has its previous significance; and with the final provisothat both the initial monosulfide and the parent dihydroxylated compoundprior to esterification be water-insoluble.

2. Hydrophile synthetic products; said hydrophile synthetic productsbeing characterized by the following formula:

in which n" is a whole number not over 2, and in which RO t is thedivalent radical obtained by the removal of the phenolic hydrogen atomsfrom an acyl phenol monosulfide of the formula i) OH HO it; is

COOH

in which n" has its previous significance; and with the final provisothat both the initial monosulfide and the parent dihydroxylated compoundprior to esterification be water-insoluble.

3. Hydrophile synthetic products; said hydrophile synhetic11 productsbeing characterized by the following orm a:

in which n" is a whole number not over 2, and in which is the divalentradical obtained by the removal of the phenolic hydrogen atoms from anacyl phenol monosulfide of the formula I? OH HO in which R1 and R2 arealkyl groups having 1 to 20 carbon atoms and R3 and R4 are identicalalkyl radicals having not more than 22 carbon atoms; 11 and n representwhole numbers which when added together equal a sum varying from 15 to80, and R is the radical of a polycarboxy acid selected from the groupconsisting of acyclic and isocyclic polycarboxy acids having not morethan 8 carbon atoms and composed of carbon, hydrogen and oxygen of theformula:

in which n" has its previous significance; and with the final provisothat both the initial monosulfide and the parent dihydroxylated compoundprior to esterification be water-insoluble.

4. Hydrophile synthetic products; said hydrophile syntfheticlproductsbeing characterized by the following ormu a:

R-O (OZHBO)1|%R(COOH)3" s it -O(GaHt0),.'iiR(000H in which n" is a wholenumber not over 2, and in which is the divalent radical obtained by theremoval of the phenolic hydrogen atoms from an acyl phenol monosulfideof the formula in which R1 and R2 are alkyl groups having 1 to 20 carbonatoms and R3 and R4 are identical alkyl radicals having at least 7 andnot over 21 carbon atoms; n and n represent whole numbers which whenadded together equal a sum varying from 15 to 80, and R is the radicalof a polycarboxy acid selected from the group consisting of acyclic andisocyclic polycarboxy acids having not more than 8 carbon atoms andcomposed of carbon, hydrogen and oxygen of the formula:

/OOOH \(OOOHLW in which n" has its previous significance; and with thefinal proviso that both the initial monosulfide and the parentdihydroxylated compound prior to esterification be water-insoluble.

5. Hydrophile synthetic products; said hydrophile syn- %het1clproductsbeing characterized by the following ormu a:

in which n" is a whole number not over 2, and in which 15 is thedivalent radical obtained by the removal of the phenolic hydrogen atomsfrom an acyl phenol monosulfide of the formula OH HO O O Rr-ii- S 91-11in which R1 and R2 are alkyl groups having 4 to 14 carbon atoms and R3and R4 are identical alkyl radicals having at least 7 and not over 21carbonatoms; n and n represent whole numbers which when addedtogethermore than 8 carbon atoms and composed of carbon, hy-

drogen and oxygen of the formula:

in which n" has its previous significance; and with the final provisothat both the initial monosulfide and the parent dihydroxylated compoundprior to esterification be water-insoluble.

6. Hydrophile synthetic products; said hydrophile synhetic1 productsbeing characterized by the following ormu a:

and in which is the divalent radical obtained by the removal of the 16phenolic hydrogen atoms from an acyl phenol monosulfide of the formula(H) OH HO 0 in which R1 and R2 are alkyl groups having 4 to 14 carbonatoms and R3 and R4 are identical alkyl radicals having at least 7 andnot over 21 carbon atoms; n and n represent whole numbers which whenadded together equal a sum varying from 15 to 80, and R is the radicalof a dicarboxy acid selected from the group consisting of acyclic andisocyclic dicarboxy acids having not more than 8 carbon atoms andcomposed of carbon, hydrogen and oxygen of the formula:

COOH \COOH said dicarboxy acid having not over 8 carbon atoms; and withthe final proviso that both the initial monosulfide and the parentdihydroxylated compound prior to esterification be water-insoluble.

7d. The product of claim 6 in which the acid is phthalic ac1 8d. Theproduct of claim 6 in which the acid is maleic ac1 9. The product ofclaim 6 in which the acid is diglycolic acid.

1d0. The product of claim 6 in which the acid is oxalic aci 111. Theproduct of claim 6 in which the acid is succinic act References Cited inthe file of this patent UNITED STATES PATENTS Number Name Date 2,319,662Cook et a1. May 18, 1943 2,562,878 Blair Aug. 7, 1951 OTHER REFERENCESRichter, Textbook of Organic Chemistry (1938 editron), page 9. JohnWiley and Sons, New York, N. Y.

1. HYDROPHILE SYNTHETIC PRODUCTS; SAID HYDROPHILE SYNTHETIC PRODUCTSBEING CHARACTERIZED BY THE FOLLOWING FORMULA: